Stitched seams

ABSTRACT

A STITCHED SEAM IN WHICH A SINGLE ROW OF SECURING STITCHES PARALLEL TO THE EDGES OF TWO PLIES OF FABRIC ALSO ANCHORS A PAIR OF EDGE COVERING THREADS EACH EXTENDING ABOUT THE EDGE OF A RESPECTIVE ONE OF THE PLIES OF FABRIC.

March 23,, 1971 s. J. KETTERER STITCHED SEAMS Filed Oct. 28, 1969 l NVEN'IOR. Stanley J. Ketterer BY WM y ATTORNEY United States PatentOffice 3,572,270 Patented Mar. 23, 1971 3,572,270 STITCHED SEAMS StanleyJ. Ketterer, Morris Plains, N.J., assignor to The Singer Company, NewYork, NY. Filed Oct. 28, 1969, Ser. No. 870,043 Int. Cl. Dc 17/00 U.S.Cl. 112-433 4 Claims ABSTRACT OF THE DISCLOSURE A stitched seam in whicha single row of securing stitches parallel to the edges of two plies offabric also anchors a pair of edge covering threads each extending aboutthe edge of a respective one of the plies of fabric.

BACKGROUND OF THE INVENTION Thisinvention relates to edge finishingseams and is particularly advantageous when used to sew together theedges of two plies of fabric which are susceptible of ravelling or ofwhich the individual fibers have poor cohesive qualities and tend toseparate readily. Under the above mentioned conditions it is known inthe art to provide each ply edge with an overedge stitch which anchorsthe fabric fibers against ravelling or separation and then to provide asecuring stitch inwardly of the edge from the overedge stitch. Usingpreviously known stitched seams, at least two separate lines ofstitching were required in order to bind each of the two ply edges withthreads and stitch the plies together. Heretofore, this could beaccomplished by passing the work several times through a plainoveredging sewing machine or by using a complicated special sewingmachine with tandem stitching mechanisms for sewing the separate seamsin one pass, as for instance is disclosed in U.S. Pat. No. 3,192,887,July 6, 1965.

SUMMARY OF THE INVENTION This invention provides for the edge stitchingof fabrics such as knit goods which can ravel or of fabrics of which thefibers can pull out easily as in the case of many fabrics woven ofsynthetic material. A single row of stitches parallel to the edges ofthe plies of fabric secures the plies together and a separate edgecovering thread is arranged back and forth over the edge of each of theplies of fabric with loops of the edge covering threads embracing thestitches in the row of securing stitches alternately between the pliesand at one side of the plies.

DESCRIPTION OF THE DRAWING The present invention is illustrated in theaccompanying drawing in which:

FIG. 1 represents a diagrammatic perspective view of the stitched seamof this invention in which the plies of work fabric are illustrated inabnormally spaced relation and in phantom lines, and in which each ofthe threads forming the seam are shown with a different shading,

FIG. 2 represents a perspective view of a fragment of work fabric formedwith a seam of this invention and in which the various threads areshaded corresponding to the shading used in FIG. 1, and

FIG. 3 is a cross sectional view taken substantially along the singlerow of stitches.

In the drawing, the upper and lower plies of fabric are designated bythe reference characters 11 and 12 respectively. Substantially parallelto the edges 11 and '12 of the fabric plies 11 and 12 respectivelyextends a row of securing stitches indicated generally at 13 andcomprising an upper thread 14 which is formed into successive loops 15-which are passed through both plies of fabric 11 and 12 at spacedintervals. Concatenated with the needle thread loops 15 beneath thefabric plies is a locking thread 16. The securing stitches 13illustrated in the drawings are two-thread chainstitches, Federal StitchType 401, but it will be understood that any other type of stitchproviding a single row of concatenated thread loops through the fabricmay be used.

For binding the edge 11' of the top fabric ply 11, an edge coveringthread 17 is formed into successive loops 18 over the upper ply 11 andloops 18 under the upper ply, i.e., the loops 18 extend between theplies 11 and 12 as clearly shown in FIG. 3. Each of the loops 18, 18embraces one of the upper thread loops 15 in the securing seam 13 andbetween the loops 18, 18' the thread extends over the edge 11' of theupper fabric ply 11.

An edge covering thread 19 is similarly provided for binding the edge 12of the lower fabric ply 12. The thread 19 is formed into successiveloops 20 under the lower ply r12 and with loops 20' over the lower ply,i.e., between the plies. Each of the loops 20, 20' embraces one of theupper thread loops 15 in the securing seam 13 and between the loops 20,20' the thread extends over the edge 12" of the lower fabric ply.

Preferably, as shown in the drawing, both edge covering threads 17 and19 embrace each loop 15 of the row of securing stitches to provide thegreatest density of edge covering stitches. The seam in accordance withthis invention, however, may be formed with either or both of the edgecovering threads engaging less than all of the securing stitch loopswith a resultant decrease in density of the threads extending over theedge of the fabric plies. It is also preferable as shown in the drawing,for only one of the edge covering threads 17 and -19 to be formed with aloop 18 or 20' extending between the plies in embracing relation withany one loop 15 of the securing seam 13'.

Having thus set forth the nature of this invention, what is claimedherein is:

1. A stitched seam for uniting the edges of two plies of fabriccomprising a row of securing stitches passing through said plies offabric parallel to the edges thereof, and a pair of edge coveringthreads each formed with successive loops embracing thread in said rowof stitches, and between said successive loops each edge covering threadextending over the edge of a respective one of said plies of fabric.

2. A stitched seam as set forth in claim '1 in which the loops formed ineach one of said pair of edge covering threads alternately embracethread in said row of securing stitches between said two plies offabric.

3. A stitched seam as set forth in claim 2 in which the loops in each ofsaid edge covering threads embrace thread in each successive stitch ofsaid row of securing stitches.

4. A stitched seam as set forth in claim 1 in which said row of securingstitches comprises an upper thread of which successive loops are passedthrough said plies of fabric from one side thereof, and a locking threadReferences Cited UNITED STATES PATENTS 3/1873 Howard et al 112433X1/1908 Weis 112436 4 Goldwyn 112269 Sandberg et al 112162 Lutz 112162Perl 112162 Reeber et al. 112162 Russell 112433 ALFRED R. GUEST, PrimaryExaminer

